<?php

/* SVN FILE: $Id$ */
/**
 * SassReturnNode class file.
 * @author      Chris Yates <chris.l.yates@gmail.com>
 * @copyright   Copyright (c) 2010 PBM Web Development
 * @license      http://phamlp.googlecode.com/files/license.txt
 * @package      PHamlP
 * @subpackage  Sass.tree
 */

/**
 * SassReturnNode class.
 * Represents a Return.
 * @package      PHamlP
 * @subpackage  Sass.tree
 */
class SassReturnNode extends SassNode
{

    const NODE_IDENTIFIER = '+';
    const MATCH = '/^(@return\s+)(.*)$/i';
    const IDENTIFIER = 1;
    const STATEMENT = 2;

    /**
     * @var statement to execute and return
     */
    private $statement;

    /**
     * SassReturnNode constructor.
     * @param object source token
     * @return SassReturnNode
     */
    public function __construct($token)
    {
        parent::__construct($token);
        preg_match(self::MATCH, $token->source, $matches);

        if (empty($matches)) {
            return new SassBoolean('false');
        }

        $this->statement = $matches[self::STATEMENT];
    }

    /**
     * Parse this node.
     * Set passed arguments and any optional arguments not passed to their
     * defaults, then render the children of the return definition.
     * @param SassContext the context in which this node is parsed
     * @return array the parsed node
     */
    public function parse($pcontext)
    {
        $return = $this;
        $context = new SassContext($pcontext);
        $statement = $this->statement;

        $parent = $this->parent->parent->parser;
        $script = $this->parent->parent->script;
        $lexer = $script->lexer;

        $result = $script->evaluate($statement, $context);

        throw new SassReturn($result);
    }

    /**
     * Returns a value indicating if the token represents this type of node.
     * @param object token
     * @return boolean true if the token represents this type of node, false if not
     */
    public static function isa($token)
    {
        return $token->source[0] === self::NODE_IDENTIFIER;
    }

}

class SassReturn extends Exception
{

    function __construct($value)
    {
        $this->value = $value;
    }

}